Smart Poly® Learning Mat 12"x17", Double-Sided, Human Body Systems & Anatomy. Front features 6 systems in the body with an explanation about what they are/ do and the Anatomy of a skeleton. Back features Human Anatomy of the eye, brain, heart, cell and ear. Heavy duty double-sided surface for fun and colorful learning on both sides. Write-on/ wipe-off surface. Use with dry erase or water based markers and washable crayons. Each side is an interactive lesson.